A pastel dial on the bracelet the Datejust was born with is a wider gap in age than it first appears. Reference 278344RBR is the 31mm Datejust in a combination of stainless steel and white gold with a domed bezel set with diamonds, and this configuration pairs a mint green dial and applied index markers with the Jubilee bracelet. The Jubilee was introduced in 1945 for the original Datejust and has been on the model ever since, and mint green arrived within the past several years, so the oldest element of the watch and the newest are sitting directly against each other with nothing in between to mediate.
The bracelet is what makes that work rather than what makes it awkward. Its five links across the width put white gold center rows between steel outer links, and because those two metals sit close enough in color that the alternation reads as a change of finish rather than of material, the wrist supplies fine construction without supplying any color of its own. The dial keeps its monopoly. The bezel above is white gold set with diamonds, covering most of the only surface where the metal distinction would otherwise be legible, which reinforces the same effect. The dial is an even lacquer applied in several thin coats to hold its tone across a curved surface, pale and cool with no depth to it, and the applied indexes are white gold and faceted, drawn for this case size rather than scaled from another. White gold is also considerably denser than steel, so the bezel is noticeably heavier than a steel one of the same dimensions. The date sits at three under the Cyclops lens on a matched disc. Rolex draws the hands for each case size rather than scaling a single set across the range, and the date frame is polished white gold set flush with the lacquer so the aperture reads as part of the dial rather than as a cut made into it. The bezel stones are seated individually into recesses cut in the gold rather than dropped into a preformed channel, and on a ring this small there is less circumference to absorb an error, so the tolerances run tighter than on a larger bezel of the same design. That extra mass sits at the outer edge of the case, where weight registers most, and it is the one way the second metal announces itself on a watch where it cannot be seen.
The date is the only indication the watch carries beyond the time. The Cyclops lens above the aperture has been part of the Datejust since 1953. The date changes instantaneously at midnight rather than creeping through the surrounding hour, the feature the model introduced in 1945 and the reason it carries the name it does. Correction runs through the winding crown without advancing the hands, hand winding uses the same crown with no separate position to learn, and nothing the watch asks for requires a tool. The movement is self-winding with a power reserve of approximately 55 hours, engineered into a movement built to fit a 31mm case rather than carried down from a larger one, since a smaller barrel stores less energy and a proportionally smaller rotor supplies less of it. The crown screws down against the case, and the Jubilee closes with a concealed clasp folded away inside the links. A movement of this size gathers less from the same wrist movement than a larger one, so the watch prefers regular wear to rotation. Correction takes seconds and requires no tool, which on a watch meant to be worn constantly matters more than the reserve figure itself. That is true of all nine grounds this reference builds, so the dial is the only place the watches differ.
The Datejust arrived in 1945 as the first self-winding wristwatch to show the date in a window, and the 31mm case sits between the 28mm Lady-Datejust and the 36mm original. The 278000 generation replaced the 178000 series in 2018 with a revised case and bracelet. For most of the model's history the dial range ran to silver, white, champagne and black, and the pastels belong entirely to the current period. Steel and white gold is the quietest two-metal combination Rolex offers, which is part of why a color this specific has so little competition on the watch. Within the generation, 278344RBR is the steel and white gold reference with a diamond-set domed bezel. Rolex casts its own gold in a foundry on its premises, which is unusual in the industry and is why it can hold an alloy to a consistent tone across decades of production. The 31mm case is also the least discussed of the three Datejust sizes and the one that has quietly absorbed most of the demand that used to go to the smaller references. Mint green is one of seven grounds this reference offers unset, and one of four never built with stones on the dial at all.
This suits a buyer who wants a current dial on a watch that is otherwise entirely traditional. The Jubilee, the case profile, the marker set and the date display would all have been familiar decades ago, and the color would not, which produces something that reads as a known object with one thing changed rather than as a new design. Buyers weighing it against the Oyster version are choosing whether the wrist should have detail of its own, and on a dial this reticent about everything except color, most people find they want it. There is a practical point as well. A lacquer dial shows no variation between examples and none over time, so a buyer knows exactly what the watch will look like a decade on, which is not something the nacre or stone dials on this reference can promise. It takes two of the reference's thirty-two rows, one per bracelet.
